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Mapping of a restriction fragment length polymorphism within the human aldolase B gene 总被引:1,自引:0,他引:1
Giovanni Paolella Rita Santamaria Pasqualina Buono Francesco Salvatore 《Human genetics》1987,77(2):115-117
Summary Peripheral blood DNA was hybridized to the full-length cDNA and the cloned structural gene of human aldolase B. With PvuII endonuclease a restriction fragment length polymorphism was detected that was present in the heterozygous state in about 21% of the individuals tested. A map of the human aldolase gene was constructed for the two groups of individuals found to produce different fragments after PvuII digestion. This allowed the localization of the polymorphic site within the gene, which was found to be due to the loss of a PvuII site in the last intron upstream from the 3 end. This polymorphism may be used as a genetic marker to study individuals affected by hereditary fructose intolerance. 相似文献
4.
Extracellular complementation of a developmental mutation implicates a small sporulation protein in aerial mycelium formation by S. coelicolor 总被引:19,自引:0,他引:19
The filamentous bacterium S. coelicolor differentiates by forming aerial hyphae, which protrude into the air and metamorphose into chains of spores. Aerial hyphae formation is associated with the production of a small, abundant protein, SapB, which is present in a zone around colonies of differentiating bacteria. Production of SapB is impaired in bld mutants, which are blocked in aerial hyphae formation, but not in whi mutants in which spore formation is prevented. We report that aerial hyphae formation by a newly identified bld mutant is restored by juxtaposition of the mutant near colonies of SapB-producing bacteria or by the application of the purified protein near mutant colonies. These observations implicate SapB in aerial mycelium formation and suggest that SapB is a morphogenetic protein that enables hyphae on the surface of colonies to grow into the air. 相似文献
5.
Pere Santamaria Michael T. Boyce-Jacino Alan L. Lindstrom Jose J. Barbosa Anthony J. Faras Stephen S. Rich 《Immunogenetics》1991,33(5-6):374-387
Nucleic acid sequences of the second exons of HLA-DRB1, –DRB3/4/5, –DQB1, and –DQA1 genes were determined from 43 homozygous cell lines, representing each of the known class II haplotypes, and from 30 unrelated Caucasian subjects, comprising 60 haplotypes. This systematic sequence analysis was undertaken in order to a) determine the existence of sequence microheterogeneity among cell lines which type as identical by methods other than sequencing; b) determine whether direct sequencing of class II genes will identify the presence of more extensive sequence polymorphism at the population level than that identified with other typing methods; c) accurately determine the molecular composition of the known class II haplotypes; and d) study their evolutionary relatedness by maximum parsimony analysis. The identification of seven previously unidentified haplotypes carrying five new allelic amino acid sequences suggests that sequence microheterogeneity at the population level may be more frequent than previously thought. Maximum parsimony analysis of these haplotypes allowed their evolutionary classification and indicates that the higher mutation rate at DRB1 compared to DQB1 loci in most haplotypic groups is inversed in specific haplotype lineages. Furthermore, the extent and localization of gene conversions and point mutations at class II loci in the evolution of these haplotypes is significantly different at each locus. Identification of additional HLA class II molecular microheterogeneity suggests that direct sequence analysis of class II HLA genes can uncover new allelic sequences in the population and may represent a useful alternative to current typing methodologies to study the effects of sequence allelism in organ transplantation.The nucleotide sequence data reported in this paper have been submitted to the GenBank nucleotide sequence database and have been assigned the accession numbers M35890 through M35953. 相似文献
6.
Cognitive schema were used to explain health and illness behaviors among Chinese students. University students in Hong Kong were asked to attribute causes and suggest solutions to five health/mental health problems: Weakness/Fatigue, Tension/ Anxiety, Sleep Difficulty, Hollow/Emptiness, and Headache. The patterns of endorsement on the causal and solution categories used for the five problems were compared using a new asymptotic chi-squared test. The response patterns were found to be significantly different across the five problems. Each problem was attributed to multiple causes including psychological, social, situational, somatic, and existential factors. The intended solutions were often related to the nature of the causal attributions especially when the problems were mild. In lay help-seeking, the Hong Kong students would attempt a variety of self-help measures. However, for professional consultation, the medical doctor would be the primary care professional the students would turn to for most of the problems except in the case of Hollow/Emptiness. 相似文献
7.
Klaas Nicolay Fanny Dorine Laterveer Waander Laurens van Heerde 《Journal of bioenergetics and biomembranes》1994,26(3):327-334
A number of amphipathic peptides were tested for their effects on structural and functional properties of isolated rat liver mitochondria. The peptides included the matrix targeting sequence of subunit IV of (yeast) cytochromec oxidase. Titration experiments in which the mitochondria were incubated with increasing concentrations of the peptides revealed two major stages in the interaction. First, at low peptide/mitochondria ratios, peptide binding to the outer membrane occurred which was accompanied by gradual lysis of the outer membrane at higher ratios. The latter was deduced from the release of adenylate kinase, the classical marker enzyme of the intermembrane space. Secondly, at still higher peptide/mitochondria ratios, the permeability of the inner membrane progressively increased, as evidenced by measurements of respiratory control and of the membrane potential. Complete uncoupling of respiration seemed to precede dissipation of the membrane potential. 相似文献
8.
Gudrun C. Hartmann Elena Santamaria Victor M. Fernández R. K. Thauer 《Journal of biological inorganic chemistry》1996,1(5):446-450
H2–forming N 5,N 10 –methylenetetrahydromethanopterin dehydrogenase is a novel type of hydrogenase that contains neither nickel nor iron-sulfur clusters. Evidence has been presented that the reaction mechanism catalyzed by the enzyme is very similar to that of the formation of carbocations and H2 from alkanes under superacidic conditions. We present here further results in support of this mechanism. It was found that the purified enzyme per se did not catalyze the conversion of para H2 to ortho H2, a reaction catalyzed by all other hydrogenases known to date. However, it catalyzed the conversion in the presence of the substrate N 5,N 10 –methenyltetrahydromethanopterin (CH≡H4MPT+), indicating that for heterolytic cleavage of H2 the enzyme-CH≡H4MPT+ complex is required. In D2O, the formation of HD and D2 from H2 rather than a para–ortho H2 conversion was observed, indicating that after heterolytic cleavage of H2 the dissociation of the proton from the enzyme-substrate complex is fast relative to the re-formation of free H2. 相似文献
9.
Christiane Guguen-Guillouzo Marie-France Szanjnert Denise Glaiser Claudine Gregori Fanny Schapira 《In vitro cellular & developmental biology. Plant》1981,17(5):369-377
Summary Aldolase and pyruvate kinase isozymes were investigated in cultured hepatocytes from fetal, regenerating, and 2-acetyl-aminofluorene-fed
rat liver as well as in some epithelial liver cell lines. Our results show that: (a) cell proliferation and prolonged expression
of specific isozymes were found only in cultured hepatocytes from 17-day old fetuses; (b) the fetal type of pyruvate kinase
expressed in regenerating and carcinogen-treated liver was temporarily lost only in cultured hepatocytes from regenerating
liver; (c) the adult type of aldolase and pyruvate kinase was absent in one epithelial cell line derived from a carcinogen-treated
liver and in the hepatoma tissue cell (HTC) line but was found in the Faza clone of the Reuber H35 cell line during the 50 first passages in vitro; and (d) the isozyme pattern of pyruvate kinase was always more strongly
shifted than that of aldolase.
The observations suggest that: (a) hepatocytes from carcinogen-treated liver exhibit the same lack of ability to proliferate
in primary culture as normal adult hepatocytes; (b) adult hepatocytes can produce fetal isozymes without prior cell division;
(c) pyruvate kinase is a stronger marker of dedifferentiation (retrodifferentiation) than aldolase; and (d) regulatory processes
of isozyme expression are different during ontogenesis, regeneration, and hepatocarcinogenesis.
This work was supported by the “Institut National de la Santé et de la Recherche Médicale” and the “Fondation pour la Recherche
Medicale Fran?aise” 相似文献
10.
Pedro Santamaria 《Molecular & general genetics : MGG》1979,172(2):161-163
Summary Heat shock of 37°C applied to Drosophila embryos at blastoderm stage induces phenocopies of some dominant mutants of the bithorax complex. Heat shock might shut down functions of cis regulator genes involved in embryonic pattern formation. 相似文献